Took me a minute to find this.. but before PC MC added native stained glass where the whole pane was colored, someone created a mod where they made the border and the flecks in the regular glass various colors...It's not true stained glass.. but it works.

That type of stained glass is easy enough to add, although in TM it would require a separate block id for each color, because TM does not store RGB color in the mesh, only texture coordinates.